Question

On a day when the atmospheric pressure is
P = 1 atm and the temperature is 22*C, a
diving bell in the shape of a cylinder 4.9mtall,
closed at the upper end, is lowered into water
to aid in the construction of an underground
foundation for a bridge tower. The water
inside the diving bell rises to within 2.3 m of
the top, and the temperature drops to 7.8*C.
The acceleration of gravity is 9.8 m/s2 .
Find the air pressure inside the bell.

How far below the surface of the water is the
bell located? (In actual use, additional air is
pumped in, forcing the water out to provide
working space for the construction workers).